1. Field of the Invention
The present invention relates to a user location tracking system (“tracking system”) and methods to locate user carried mobile devices, such as those used in digital cellular systems, personal communications systems (“PCS”), enhanced specialized mobile radios (“ESMRs”), radio frequency (“RF”) based tracking systems (Bluetooth, WiFi), and other wireless communications systems. More particularly, but not exclusively, the present disclosure relates to methods that employ the location of the individually tracked user to determine the time at which the user arrives (“arrival time”) at a monitored space, including the corresponding rented room at a hotel (“rented room”), the total number of tracked users at a hotel for control of the rented room related conditions.
2. Background
A residing guest (“user”) at a hotel contributes to energy consumption in the use of a rented room through two primary utility sources: Heating, Ventilating and Air-Conditioning system (“HVAC”) and heated water. In conventional HVAC systems, the temperature within a rented room is raised or lowered at multiple operating levels. The indoor temperature is typically maintained at three different levels. The setpoint level is often selected by the user when the rented room is attended. The comfort level is maintained at a few degrees from the setpoint temperature for energy conservation when the rented room is unoccupied while allowing speedy resume to the setpoint level. The free level is used for maximal energy conservation of an unrented room.
Common problem of the comfort level often being the setback temperature either too far away from the setpoint temperature to provide satisfactory comfort when someone returns to the unoccupied monitored space, or too close to the setpoint temperature to achieve adequate energy savings. Indoor temperature at comfort level requires a drive time to be resumed to setpoint temperature; the corresponding estimated minimal required drive time is therefore overly inaccurate. The “Short Cycling” phenomenon may result from insufficient operating times, leading to overshooting the user's setpoint temperature and unbounded up/down temperature cycles within a given time period. The result is unavoidable damage to the HVAC system and shortening of the general operative life span.
In addition to indoor temperature setpoint control, heated water at setpoint temperature must also be readily supplied to the rented rooms. Water heaters fall into one of two categories: 1. tankless type water heaters, and 2. storage tank type water heaters. The hotel usually keeps a track record for heated water consumption regardless of the type of water heater used. Consumption of heated water greatly varies within different times of the day and during different seasons of the year notwithstanding, the volume is also dependent on the number of tracked users being onsite. Should the heated water supply be planned on basis of the projected number of tracked users being at the hotel during the day, the volume of heated water allocated on the per user basis can be maintained at an interrelated level.
In addition, the information related to each projected user's arrival time at the monitored space, the occupancy status being attended or unattended by the user, may also be used for provision of house watching services.